Vacuum cleaner

ABSTRACT

A vacuum cleaner includes a suction head including a cover and a bottom plate provided with a suction hole through which air is sucked from a surface to be cleaned and rotatably combined with the cover. The bottom plate is rotated in one direction relative to the cover when the suction head moves forward, and is rotated in the other direction relative to the cover when the suction head moves backward. Further, the vacuum cleaner includes a brush base including brushes and movable upward and backward between the cover and the bottom plate. The brush base includes indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Patent Application No. 10-2012-0110306, filed on Oct. 4, 2012 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND

1. Field

One or more embodiments relate to a vacuum cleaner which separates and collects dust from air sucked by suction force of a fan motor and has a suction head closely adhered to a surface to be cleaned and sucking air.

2. Description of the Related Art

In general, a vacuum cleaner includes a fan motor generating suction force, a suction head closely adhered to a surface to be cleaned and sucking air by the suction force of the fan motor, and a dust collector separating dust from the air sucked through the suction head and collecting the separated dirt, and thus performing cleaning.

The fan motor and the dust collector may be accommodated in a main body, and the suction head may be connected to the main body by an extension pipe and may move to positions requiring cleaning on the surface to be cleaned.

The suction head may include a bottom plate provided with a suction hole, a brush base provided with brushes and preventing damage, such as scratches, to the bottom plate or the surface to be cleaned by friction between the bottom plate and the surface to be cleaned, and a cover covering the bottom plate and the brush base and forming the external appearance of the suction head.

The brush base may move upward and downward, as needed. Therefore, the brush base may move downward if the vacuum cleaner cleans a relatively hard surface, such as a hard floor, and move upward if the vacuum cleaner cleans a relatively soft surface, such as a carpet. However, since the brush base is covered by the cover and is thus not exposed to the outside, detection of the position of the brush base is not easy.

Further, when cleaning is performed while moving the suction head forward, operation of the suction head is not easy due to resistance of the surface to be cleaned. That is, large operation force is required to move the suction head forward. Further, when cleaning is performed while moving the suction head backward, if the rear end of the suction head is lifted up, the suction hole is not closely adhered to the surface to be cleaned, and thus suction force may be lowered.

SUMMARY

The foregoing described problems may be overcome and/or other aspects may be achieved by one or more embodiments of a vacuum cleaner that may have a suction head which may be configured such that the position of an upward and downward movable brush base may be recognized from the outside.

One or more embodiments provide a vacuum cleaner having a suction head which may be configured such that operation force of the suction head may be reduced when the suction head moves forward.

One or more embodiments provide a vacuum cleaner that may have a suction head which may be configured such that suction force of the suction head may not be reduced when the suction head moves backward.

Additional aspects and/or advantages of one or more embodiments will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of one or more embodiments of disclosure. One or more embodiments are inclusive of such additional aspects.

In accordance with one or more embodiments, a vacuum cleaner may include a main body, a fan motor provided within the main body and generating suction force, a dust collector provided within the main body and collecting dust, an extension pipe extended from the main body, and a suction head including a cover combined with the extension pipe, and a bottom plate provided with a suction hole through which air may be sucked from a surface to be cleaned and rotatably combined with the cover, wherein the bottom plate may be rotated in a first direction relative to the cover when the suction head moves forward, and may be rotated in a second direction opposite the first direction relative to the cover when the suction head moves backward.

The first direction may be the counterclockwise direction and the second direction may be the clockwise direction, as seen from a direction in which the front end of the suction head is located at the left and the rear end of the suction head is located at the right.

A rotary shaft may be formed on one of the cover and the bottom plate, and a rotary shaft receiving part in which the rotary shaft is accommodated so as to be freely rotatable may be formed on the other of the cover and the bottom plate.

The bottom plate may be rotated in the first direction relative to the cover by friction with the surface to be cleaned, when the suction head moves forward.

The bottom plate may be rotated in the second direction relative to the cover by reaction force of the surface to be cleaned applied to the front end of the bottom plate or the weight of the bottom plate, if the cover is rotated in a direction in which the rear end of the cover is separated from the surface to be cleaned when the suction head moves backward.

The suction hole may include a suction space in which air flows, and a diaphragm part protruding toward the cover to form the suction space.

The diaphragm part may include a sealing part closely adhered to an inlet of a suction duct to guide the sucked air to the inside of the suction duct without leaking to the outside of the suction duct, and the sealing part may include a curved part curved so as to be closely adhered to the inlet of the suction duct in spite of a rotation of the bottom plate.

Stopper protrusions interfering with the cover to limit the rotating range of the bottom plate may be formed on the diaphragm part.

In accordance with one or more embodiments, a vacuum cleaner may include a main body, a fan motor provided within the main body and generating suction force, a dust collector provided within the main body and collecting dust, an extension pipe extended from the main body, and a suction head including a cover combined with the extension pipe, a bottom plate provided with a suction hole through which air may be sucked from a surface to be cleaned and combined with the cover, and a brush base including brushes and movable upward and downward between the cover and the bottom plate, wherein the brush base may include indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head.

The indicating parts may be formed at corners of the brush base.

The cover may include cutoff slots in which the indicating parts are accommodated.

The indicating parts may be movable upward and downward in the cutoff slots.

The suction head may be switched to one of a first mode in which the brush base moves maximally upward closest to the cover so that the bottom plate is closely adhered to the surface to be cleaned, and a second mode in which the brush base moves maximally downward closest to the bottom plate so that the brushes are closely adhered to the surface to be cleaned.

A height difference between the indicating parts and the cover may not be generated in the first mode, and a height difference between the indicating parts and the cover may be generated in the second mode.

The vacuum cleaner may further include a lever member rotatably provided to move the brush base upward and downward and including pressing protrusions pressing the brush base and an operating member to rotate the lever member.

The vacuum cleaner may further include elastic members elastically supporting the brush base.

In accordance with one or more embodiments, a vacuum cleaner may include a main body, a fan motor provided within the main body and generating suction force, a dust collector provided within the main body and collecting dust, an extension pipe extended from the main body, and a suction head including a cover combined with the extension pipe, a bottom plate provided with a suction hole through which air may be sucked from a surface to be cleaned and rotatably combined with the cover, and a brush base that may include brushes and indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head and movable upward and downward between the cover and the bottom plate, wherein the suction head may be switched to one of a first mode in which the brush base moves maximally upward closest to the cover so that the bottom plate is closely adhered to the surface to be cleaned, and a second mode in which the brush base moves maximally downward closest to the bottom plate so that the brushes are closely adhered to the surface to be cleaned, and the bottom plate may be rotated in a first direction relative to the cover when the suction head moves forward, and may be rotated in a second direction opposite the first direction relative to the cover when the suction head moves backward, in the first mode.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readily appreciated from the following description of embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a perspective view illustrating a vacuum cleaner in accordance with one or more embodiments;

FIG. 2 is a view illustrating a suction head of a vacuum cleaner according to one or more embodiments, such as the vacuum cleaner of FIG. 1, in a state in which the suction head is in a first mode;

FIG. 3 is an exploded perspective view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2, as seen from one angle;

FIG. 4 is an exploded perspective view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2, as seen from another angle;

FIG. 5 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 taken along the line I-I of FIG. 2;

FIG. 6 is a view illustrating rotation of a bottom plate of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 when the suction head moves forward;

FIG. 7 is a view illustrating rotation of a bottom plate of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 when the suction head moves backward;

FIG. 8 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 taken along the line II-II of FIG. 2;

FIG. 9 is a view illustrating a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 1, in a state in which the suction head is in a second mode; and

FIG. 10 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 9 taken along the line III-III of FIG. 9.

DETAILED DESCRIPTION

Reference will now be made in detail to one or more embodiments, illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, embodiments of the present invention may be embodied in many different forms and should not be construed as being limited to embodiments set forth herein, as various changes, modifications, and equivalents of the systems, apparatuses and/or methods described herein will be understood to be included in the invention by those of ordinary skill in the art after embodiments discussed herein are understood. Accordingly, embodiments are merely described below, by referring to the figures, to explain aspects of the present invention.

FIG. 1 is a perspective view illustrating a vacuum cleaner in accordance with one or more embodiments.

With reference to FIG. 1, a vacuum cleaner 1 in accordance with the embodiment of the present invention may include a main body 20 in which a fan motor 21 that may generate suction force and a dust collector 22 that may separate dust from sucked air and may collect the separated dust may be accommodated, a suction head 100 mat may suck air from a surface to be cleaned, and an extension pipe 10 that may connect the suction head 100 to the main body 20 to guide the air sucked through the suction head 100 to the main body 20.

The dust collector 22 may be of a cyclone type which separates dust from sucked air using centrifugal force, or a dust bag type which filters out dust from sucked air by causing air to pass through a filter bag. Otherwise, the dust collector 22 may be of one of various known types which may separate dust from sucked air. Purified air from which dust is separated through the dust collector 22 may be discharged to the outside of the main body 20.

The extension pipe 10 may include an extension pipe 12 having a designated rigidity, an extension hose 13 connecting the extension pipe 12 to the main body 20 and having flexibility, a connector 11 connecting the suction head 100 to the extension pipe 12, and a handle 14. The connector 11 may be combined with the suction head 100 so as to be rotatable by a designated angle, and may be provided with wheels 15 (see FIG. 2) to facilitate movement of the suction head 100.

The suction head 100 may be closely adhered to a surface to be cleaned and may serve to suck air from the surface to be cleaned. The suction head 100 of the vacuum cleaner 1 in accordance with one or more embodiments may be switched to one of a first mode and a second mode so as to possibly prevent damage due to friction with the surface to be cleaned or to possibly increase suction force according to kind, material and state of the surface to be cleaned.

The first mode is a mode to possibly increase suction force if the surface to be cleaned is formed of a soft fabric, such as a carpet, and the second mode is a mode to possibly prevent damage, such as scratches, to the suction head 100 or the surface to be cleaned due to friction with the surface to be cleaned if the surface to be cleaned is formed of a hard material, such as a floor.

Further, the suction head 100 in accordance with the embodiment of the present invention may be configured such that a user may recognize whether or not the suction head 100 is currently in the first mode or the second mode.

The suction head 100 in accordance with one or more embodiments may be configured such that operation of the suction head 100 may be enhanced when the suction head 100 moves forward and a decrease in suction force of the suction head 100 may be prevented when the suction head 100 moves backward, in the first mode used on carpet, etc.

Hereinafter, a configuration of the suction head 100 of the vacuum cleaner 10 in accordance with one or more embodiments will be described in detail.

FIG. 2 is a view illustrating a suction head of a vacuum cleaner according to one or more embodiments, such as the vacuum cleaner of FIG. 1, in a state in which the suction head is in the first mode, FIG. 3 is an exploded perspective view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2, as seen from one angle, FIG. 4 is an exploded perspective view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2, as seen from another angle, FIG. 5 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 taken along the line I-I of FIG. 2, FIG. 6 is a view illustrating rotation of a bottom plate of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 when the suction head moves forward, FIG. 7 is a view illustrating rotation of a bottom plate of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 when the suction head moves backward, FIG. 8 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 2 taken along the line II-II of FIG. 2, FIG. 9 is a view illustrating a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 1, in a state in which the suction head is in the second mode, and FIG. 10 is a cross-sectional view of a suction head according to one or more embodiments, such as the suction head of the vacuum cleaner of FIG. 9 taken along the line of FIG. 9.

With reference to FIGS. 2 to 10, the suction head 100 may include a cover 200 combined with the connector 11, a bottom plate 600 provided with a suction hole 640 through which air may be sucked from the surface to be cleaned and rotatably combined with the cover 200, a brush base 400 including brushes 450 and provided between the cover 200 and the bottom plate 600 so as to be movable upward and downward, a lever member 300 moving the brush base 400, and elastic members 500 elastically supporting the brush base 400.

The cover 200 may be disposed above the lever member 300, the brush base 400, the elastic members 500 and the bottom plate 600, and may form most of the external appearance of the suction head 100.

A first rotary shaft 230 and a second rotary shaft receiving part 240 may be formed on the cover 200, and a first rotary shaft receiving part 620 and a second rotary shaft 610 may be formed on the bottom plate 600.

The first rotary shaft 230 may be accommodated in the first rotary shaft receiving part 620 so that the first rotary shaft 230 may be freely rotatable, and the second rotary shaft 610 may be accommodated in the second rotary shaft receiving part 240 so that the second rotary shaft 610 may be freely rotatable.

The first rotary shaft 230 and the second rotary shaft 610 may be formed collinearly. That is, an extension line of the first rotary shaft 230 and an extension line of the second rotary shaft 610 may be the same straight line, and thus may form one rotary shaft. Through such a configuration, the bottom plate 600 may be rotated relative to the cover 200 by external force.

Guide bars 260 may be formed on the cover 200, and guide holes 430 may be formed on the brush base 400. The guide bars 260 may protrude from the cover 200 toward the bottom plate 600, and may pass through the guide holes 430. Through such a configuration, the brush base 400 may be supported by the guide bars 260 and may move upward and downward between the cover 200 and the bottom plate 600.

The brush base 400 may be elastically supported by the elastic members 500. The elastic members 500 may be coil springs, for example. Elastic member mounting parts 440 may be formed on the brush base 400, and mounting protrusions 630 may be formed on the bottom plate 600. The elastic member mounting part 440 may be formed on the surface of the brush base 400 opposite the guide holes 430.

The elastic members 500 may be mounted between the elastic member mounting parts 440 and the mounting protrusions 630, and be supported by the guide bars 260 passing through the guide holes 430.

The position of the brush base 400 elastically biased by elastic force of the elastic members 500 may be the position of the brush base 400 in the first mode of the suction head 100. Here, the position of the brush base 400 in the first mode of the suction head 100 may be the position of the brush base 400 which may move upward toward the cover 200.

The brush base 400 may move to the position of the brush base 400 in the second mode of the suction head 100 by the lever member 300. Here, the position of the brush base 400 in the second mode of the suction head 100 may be the position of the brush base 400 which may move downward toward the bottom plate 600.

A third rotary shaft 310 may be formed on the lever member 300 and a third rotary shaft receiving part 250 may be formed on the cover 200. The third rotary shaft 310 may be accommodated in the third rotary shaft receiving part 250 so that the third rotary shaft 310 may be freely rotatable.

An operating member 320 rotating the lever member 300 may be formed on the lever member 300, and an opening 220 exposing the operating member 320 to the outside may be formed on the cover 200. Therefore, a user may rotate the lever member 300 by pressing the operating member 320.

When the user presses the operating member 320, the lever member 300 may be rotated about the third rotary shaft 310. The operating member 320 may include a first operation part 321 to rotate the lever member 300 in one direction, and a second operation part 322 to rotate the lever member 300 in the other direction.

Pressing protrusions 330 to press the brush base 400 may be formed on the lever member 300. The pressing protrusions 330 may be accommodated in active parts 490 of the brush base 400.

As shown in FIGS. 8 and 10, a first support surface 491, an inclined surface 492 and a second support surface 493 may be continuously formed on the brush base 400. The first support surface 491 may be formed more distant from the third rotary shaft 310 than the second support surface 493, and the inclined surface 492 may connect the first support surface 491 and the second support surface 493. The first support surface 491, the inclined surface 492 and the second support surface 493 may be pressed by the pressing protrusions 330.

FIG. 8 illustrates the first mode of the suction head 100, i.e., a case in which the brush base 400 is located at a position moving upward toward the cover 200, and the pressing protrusions 330 may be supported by the first support surface 491 being most distant from the third rotary shaft 310. Here, the brush base 400 may be elastically supported by the elastic members 500.

FIG. 10 illustrates the second mode of the suction head 100, i.e., a case in which the brush base 400 is located at a position moving downward toward the bottom plate 600. As shown in FIG. 10, when a user presses the second operation part 322 in the downward direction (direction D), the lever member 300 may be rotated about the third rotary shaft 310.

At this time, the pressing protrusions 330 may also be rotated about the third rotary shaft 310, and sequentially may press the first support surface 491, the inclined surface 492 and the second support surface 493. When the pressing protrusions 330 finally press the second support surface 493, the state of the brush base 400 may be fixed by pressing force of the pressing protrusions 330 against elastic force of the elastic members 500. Through such an operation, the suction head 100 may be switched from the first mode to the second mode.

With reference to FIG. 8, when a user presses the first operation part 321 in the downward direction (direction D) in the second mode of the suction head 100, the lever member 300 may be rotated about the third rotary shaft 310 and the pressing protrusions 330 may also be rotated about the third rotary shaft 310.

As the pressing protrusions 330 are rotated, the brush base 400 may be raised by elastic force of the elastic members 500, and the pressing protrusions 330 may be supported by the first support surface 491. Thereby, the brush base 400 may be fixed. Through such an operation, the suction head 100 may be switched from the second mode to the first mode.

A suction hole 640 through which air is sucked from the surface to be cleaned may be formed on the bottom plate 600. The suction hole 640 may include a suction space 641 in which air flows, and a diaphragm part 642 protruding toward the cover 200 to form the suction space 641.

Guide channels 650 to guide air to the suction hole 640 may be formed on the lower surface of the bottom plate 600. The guide channels 650 may be formed in the lengthwise direction of the bottom plate 600 at both sides of the suction hole 640.

A through hole 410 through which the suction hole 640 may pass may be formed on the brush base 400, and a suction duct 210 to guide air sucked through the suction hole 640 to the extension pipe 10 may be formed on the cover 200. The suction hole 640 may pass through the through hole 410 and be connected to the suction duct 210.

Further, as shown in FIGS. 5 to 7, the diaphragm part 642 may include a sealing part 643 closely adhered to an inlet 211 of the suction duct 210 to guide sucked air to the inside of the suction duct 210 instead of to the outside of the suction duct 210. Here, the sealing part 643 may include a curved part 644 curved gently.

Through such a configuration, even if the bottom plate 600 is rotated relative to the cover 200, the diaphragm part 642 may be closely adhered to the inlet 211 of the suction duct 210, and thus air sucked through the suction hole 640 may be guided to the inside of the suction duct 210 without leaking.

Further, stopper protrusions 645 limiting the rotating range of the bottom plate 600 may be formed on the diaphragm part 642. The stopper protrusions 645 may interfere with the cover 200, thus limiting the rotating range of the bottom plate 600. In contrast, the stopper protrusions 645 may be formed on the cover 200 so as to interfere with the bottom plate 600.

The brush base 400 may include the brushes 450, a front blocking member 460 and a rear blocking member 470.

The lowest point of the brushes 450, the front blocking member 460 and the rear blocking member 470 may be located above the lowest point of the bottom plate 600 in the first mode of the suction head 100 in which the brush base 400 moves upward, and may be located below the lowest point of the bottom plate 600 in the second mode of the suction head 100 in which the brush base 400 moves downward.

Therefore, when the brush head 100 is in the first mode, the bottom plate 300 may contact the surface to be cleaned, and when the brush head 100 is in the second mode, the brush 450, the front blocking member 460 and the rear blocking member 470 may contact the surface to be cleaned and the bottom plate 300 may be separated from the surface to be cleaned.

The front blocking member 460 and the rear blocking member 470 may seal the circumference of the suction hole 640 of the bottom plate 600 and may increase suction force in the second mode of the suction head 100 in which the brush base 400 moves downward, and may be formed of a soft material so that dust having a slightly large particle size may pass through the front blocking member 460 and the rear blocking member 470. The front blocking member 460 and the rear blocking member 470 may have passage holes 461 and 471 through which air flows into the suction hole 640.

Next, with reference to FIGS. 6 and 7, rotation of the bottom plate 600 of the suction head 100 of the vacuum cleaner in accordance with one or more embodiments relative to the cover 200 will be described in more detail.

In FIGS. 6 and 7, F means the forward movement direction of the suction head 100, and R means the backward movement direction of the suction head 100. Further, A means the rotation direction of the bottom plate 600 relative to the cover 200 when the suction head 100 moves forward, and B means the rotation direction of the bottom plate 600 relative to the cover 200 when the suction head 100 moves backward.

As shown in FIG. 6, when the brush base 400 moves upward and the suction head 100 moves forward (F) in the first mode of the bottom plate 600 in which the bottom plate 600 directly contacts the surface to be cleaned, the bottom plate 600 may be rotated in the direction A about the first rotary shaft 230 and the second rotary shaft 610 relative to the cover 200.

The reason for rotation of the bottom plate 600 relative to the cover 200 is that the bottom plate 600 is combined with the cover 200 so as to be freely rotatable and friction resistance from the surface to be cleaned is applied to the bottom plate 600 when the suction head 100 moves forward, as described above.

Through rotation of the bottom plate 600, the rear end of the bottom plate 600 may be slightly separated from the surface to be cleaned and friction resistance of the surface to be cleaned applied to the bottom plate 600 mat be reduced. Therefore, operation force required to move the suction head 100 forward may be reduced.

As shown in FIG. 7, if the cover 200 is rotated by a designated angle θ relative to the surface to be cleaned when the brush base 400 moves upward and the suction head 100 moves backward (R) in the first mode of the bottom plate 600 in which the bottom plate 600 directly contacts the surface to be cleaned, the bottom plate 600 may be rotated in the direction B about the first rotary shaft 230 and the second rotary shaft 610 relative to the cover 200.

The reason for rotation of the bottom plate 600 relative to the cover 200 is that the bottom plate 600 is combined with the cover 200 so as to be freely rotatable and, when the cover 200 is rotated by a designated angle θ relative to the surface to be cleaned, reaction force may be applied to the front end of the bottom plate 600 by the surface to be cleaned. Further, even if the cover 200 is rotated, the bottom plate 600 may not be rotated due to the weight thereof, and rotation of the bottom plate 600 relative to the cover 200 may be carried out.

Even if the cover 200 is rotated in a direction in which the rear end of the cover 200 is separated from the surface to be cleaned, as described above, the bottom plate 600 may be rotated in the opposite direction relative to the cover 200 and may be closely adhered to the surface to be cleaned, and thus lowering of suction force may be prevented.

Next, with reference to FIGS. 2 to 4 and FIG. 9, a mode recognition structure of the suction head 100 of the vacuum cleaner in accordance with the embodiment of the present invention will be described.

As described above, the suction head 100 of the vacuum cleaner in accordance with one or more embodiments may be switched to one of the first mode in which the brush base 400 moves upward toward the cover 200 and the second mode in which the brush base 400 moves downward toward the bottom plate 600.

Here, the brush base 400 may include indicating parts 480 exposed to the outside of the cover 200 and forming at least a portion of the external appearance of the suction head 100. Cutoff slots 270 accommodating the indicating parts 480 may be formed on the cover 200, and the indicating parts 480 may move upward and downward within the cutoff slots 270.

The indicating parts 480 may protrude upward from regions of the brush base 400, and for example, in one or more embodiments, the indicating parts 480 may be formed at corners of the brush base 400.

As shown in FIG. 2, the indicating parts 480 may be provided so as not to have a height difference with the cover 200 in the first mode of the suction head 100. On the other hand, as shown in FIG. 9, the indicating parts 480 may be provided so as to have a height difference H with the cover 200 in the second mode of the suction head 100. Therefore, a user may recognize the current position of the brush base 400 and the mode of the suction head 100.

As is apparent from the above description, in a vacuum cleaner in accordance with one or more embodiments, the position of a brush base in which brushes are installed may be recognized from the outside.

Further, when a suction head moves forward, operation force of the suction head may be reduced.

Further, when the suction head moves backward, lowering of suction force may be prevented even if the rear end of the suction head is lifted upward from a surface to be cleaned.

While aspects of the present invention have been particularly shown and described with reference to differing embodiments thereof, it should be understood that these embodiments should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in the remaining embodiments. Suitable results may equally be achieved if the described techniques are performed in a different order and/or if components in a described system, architecture, device, or circuit are combined in a different manner and/or replaced or supplemented by other components or their equivalents.

Thus, although a few embodiments have been shown and described, with additional embodiments being equally available, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. 

What is claimed is:
 1. A vacuum cleaner comprising: a main body; a fan motor provided within the main body and generating suction force; a dust collector provided within the main body and collecting dust; an extension pipe extended from the main body; and a suction head comprising a cover combined with the extension pipe, and a bottom plate provided with a suction hole through which air is sucked from a surface to be cleaned and rotatably combined with the cover, wherein the bottom plate is rotated in a first direction relative to the cover when the suction head moves forward, and is rotated in a second direction opposite the first direction relative to the cover when the suction head moves backward.
 2. The vacuum cleaner according to claim 1, wherein the first direction is the counterclockwise direction and the second direction is the clockwise direction, as seen from a direction in which the front end of the suction head is located at the left and the rear end of the suction head is located at the right.
 3. The vacuum cleaner according to claim 1, wherein: a rotary shaft is formed on one of the cover and the bottom plate; and a rotary shaft receiving part in which the rotary shaft is accommodated so as to be freely rotatable is formed on the other of the cover and the bottom plate.
 4. The vacuum cleaner according to claim 1, wherein the bottom plate is rotated in the first direction relative to the cover by friction with the surface to be cleaned, when the suction head moves forward.
 5. The vacuum cleaner according to claim 1, wherein the bottom plate is rotated in the second direction relative to the cover by reaction force of the surface to be cleaned applied to the front end of the bottom plate or the weight of the bottom plate when the suction head moves backward.
 6. The vacuum cleaner according to claim 1, wherein the suction hole comprises a suction space in which air flows, and a diaphragm part protruding toward the cover to form the suction space.
 7. The vacuum cleaner according to claim 6, wherein: the diaphragm part comprises a sealing part closely adhered to an inlet of a suction duct to guide the sucked air to the inside of the suction duct; and the sealing part includes a curved part curved so as to be closely adhered to the inlet of the suction duct during rotation of the bottom plate.
 8. The vacuum cleaner according to claim 6, wherein stopper protrusions interfering with the cover to limit the rotating range of the bottom plate are formed on the diaphragm part.
 9. A vacuum cleaner comprising: a main body; a fan motor provided within the main body and generating suction force; a dust collector provided within the main body and collecting dust; an extension pipe extended from the main body; and a suction head comprising a cover combined with the extension pipe, a bottom plate provided with a suction hole through which air is sucked from a surface to be cleaned and combined with the cover, and a brush base comprising brushes and movable upward and downward between the cover and the bottom plate, wherein the brush base comprises indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head.
 10. The vacuum cleaner according to claim 9, wherein the indicating parts are formed at corners of the brush base.
 11. The vacuum cleaner according to claim 9, wherein the cover comprises slots in which the indicating parts are accommodated.
 12. The vacuum cleaner according to claim 11, wherein the indicating parts are movable upward and downward in the slots.
 13. The vacuum cleaner according to claim 9, wherein the suction head is switched to one of a first mode in which the brush base moves upward toward the cover so that the bottom plate is closely adhered to the surface to be cleaned, and a second mode in which the brush base moves downward toward the bottom plate so that the brushes are closely adhered to the surface to be cleaned.
 14. The vacuum cleaner according to claim 13, wherein a height difference between the indicating parts and the cover is not generated in the first mode, and a height difference between the indicating parts and the cover is generated in the second mode.
 15. The vacuum cleaner according to claim 9, further comprising a lever member rotatably provided to move the brush base upward and downward, the lever member comprising pressing protrusions pressing the brush base and an operating member to rotate the lever member.
 16. The vacuum cleaner according to claim 9, further comprising elastic members elastically supporting the brush base.
 17. A vacuum cleaner comprising: a main body; a fan motor provided within the main body and generating suction force; a dust collector provided within the main body and collecting dust; an extension pipe extended from the main body; and a suction head comprising a cover combined with the extension pipe, a bottom plate provided with a suction hole through which air is sucked from a surface to be cleaned and rotatably combined with the cover, and a brush base comprising brushes and indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head and movable upward and downward between the cover and the bottom plate, wherein the suction head is switched to one of a first mode in which the brush base moves maximally upward closest to the cover so that the bottom plate is closely adhered to the surface to be cleaned, and a second mode in which the brush base moves maximally downward closest to the bottom plate so that the brushes are closely adhered to the surface to be cleaned, and wherein the bottom plate is rotated in a first direction relative to the cover when the suction head moves forward, and is rotated in a second direction opposite the first direction relative to the cover when the suction head moves backward, in the first mode.
 18. A suction head for a vacuum cleaner comprising: a cover combined with the extension pipe; a bottom plate provided with a suction hole through which air is sucked from a surface to be cleaned and combined with the cover; and a brush base comprising brushes and movable upward and downward between the cover and the bottom plate, wherein the bottom plate is rotated in a first direction relative to the cover when the suction head moves forward, and is rotated in a second direction opposite the first direction relative to the cover when the suction head moves backward.
 19. The suction head according to claim 18, wherein the brush base comprises indicating parts exposed to the outside of the cover and forming at least a portion of the external appearance of the suction head.
 20. The suction head according to claim 18, wherein the suction head is switched to one of a first mode in which the brush base moves upward toward the cover so that the bottom plate is closely adhered to the surface to be cleaned, and a second mode in which the brush base moves downward toward the bottom plate so that the brushes are closely adhered to the surface to be cleaned.
 21. The suction head according to claim 18, further comprising a lever member rotatably provided to move the brush base upward and downward, the lever member comprising pressing protrusions pressing the brush base and an operating member to rotate the lever member.
 22. The vacuum cleaner according to claim 18, wherein the bottom plate is rotated in a first direction relative to the cover by friction with the surface to be cleaned, when the suction head moves forward, and wherein the bottom plate is rotated in a second direction relative to the cover by reaction force of the surface to be cleaned applied to the front end of the bottom plate or the weight of the bottom plate when the suction head moves backward. 